Surface Modification of LaNi_0.6Fe_0.4O_3-δ Film Electrode by Ce_0.9Gd_0.1O_1.95 Porous Layer

Abstract

The Ce 0.9 Gd 0.1 O 1.95 porous layer was deposited into the top of LaNi 0.6 Fe 0.4 O 3-δ film electrode and compared to the bare LaNi 0.6 Fe 0.4 O 3-δ film electrode to determine the surface oxygen exchange rate. The measurement has been done by electrochemical impedance spectroscopy and isotope exchange experiment under various temperatures and oxygen partial pressures. The surface oxygen exchange rate of LaNi 0.6 Fe 0.4 O 3-δ film - Ce 0.9 Gd 0.1 O 1.95 porous layer was enhanced compared to the bare LaNi 0.6 Fe 0.4 O 3-δ film electrode. The role of Ce 0.9 Gd 0.1 O 1.95 was the promotion of incorporation step on the oxygen reduction process in the electrode as the reason of the enhancement of surface oxygen exchange rate. An Auger electron spectroscopy measurement has been done to investigate the compositional change at the LaNi 0.6 Fe 0.4 O 3-δ film surface. No compositional change was observed on the LaNi 0.6 Fe 0.4 O 3-δ film surface which can be associated to the enhancement of surface oxygen exchange rate.